UV Piscium and the Radiative Flux Scale

Abstract

Studies of eclipsing binaries with Hipparcos parallaxes are found to define a radiative flux relation for main sequence stars in the spectral range from B6 – F0which is about as well as to the stars derived from angular diameters. At lower temperatures the fluxes of the components fall below this curve which is caused due to the large intrinsic variations and starspots. From the present analysis it is found that the secondary component of UV Piscium, a late type eclipsing binary, is a normal K3V star and it fits the radiative flux-colour relation quite satisfactorily. This is explained due to the reliable values of the fluxes and colours derived from the clean light curves (light curves obtained after removing the effect of the distortion wave). However, the primary component which is also responsible for the intrinsic variations and starspots continue to deviate from this curve.